How societies are defined by the segmentation of time
Ever wondered why an hour lasts 60 minutes? How we think of time not only depends on where, but the age in which we live, writes Caleb Everett
Why does an hour last 60 minutes? Why does a minute last 60 seconds? We use these units because some of the first people to make precise astronomical calculations, the Babylonians, utilised a base-60 (sexagesimal) number system that they inherited from a more ancient population in Mesopotamia, the Sumerians. The Sumerian base-60 system proved influential on Babylonian and Greek astronomers and, because of this influence, it was later used by Europeans to divide hours into 60 equal units.
But, some might say, “hours” themselves are real, given to us by nature. Yet these time units, too, are a linguistic remnant. When sundials were first developed in ancient Egypt, their creators relied on a base-10 (decimal) system wherein 10 serves as a recurring element within larger verbal numbers (“thirty-one”, “forty-one”, etc.) As a result, their sundials broke up the day’s shadows into 10 units. Egyptians added two units to represent the times around sunrise and sunset. The resultant 12-unit system was acquired by various cultures and eventually applied to both days and nights to yield a diurnal cycle with 24 major segments.
If all of this seems arbitrary, that is because it is. There is an astronomical basis for dividing time into years and days. But most temporal units came into existence only because of the features of particular linguistic and mathematical systems. Time seems objective, as if it transcends our socio-cultural environment. But the ways we think of time depend profoundly on the place — and time — in which we live.
Temporal conventions are given to us so early in our development that a person may not remember his or her life before it was dissected into weeks, hours and minutes. From infancy, linguistically contingent cognitive implements sculpt the way we experience the passing of time.
The numbers that we use to keep track of time differ dramatically across languages and cultures. For example, number systems vary with respect to their bases. While ancient Mesopotamians relied on a sexagesimal system, most cultures have come to rely on decimal systems like the Egyptians’ or ours or, less frequently, base20 (vigesimal) systems like that employed by the Maya.
The Mayan calendar had 20 names for days, in contrast to our seven, because of the vigesimal nature of Mayan numbers. The popularity of decimal and vigesimal systems owes itself to a non-temporal feature in nature, the quantity of our fingers and toes, but many other kinds of numbers exist, including the base-6 (senary) systems found in some languages of New Guinea. Had ancient Egyptians used a senary system, our days might have 16 hours instead of 24, since daylight could have first been divided into eight (6+2) units instead of twelve.
Some languages rely on restricted number systems without any bases at all. These include the “one-two-many” systems of some populations in Amazonia and Australia. Some hunter-gatherers do not use any precise numbers. Research by cognitive scientists has shown that such numberless adults do not exactly differentiate quantities greater than three. Instead, they rely on the approximation of most quantities in their day-to-day lives.
“One-two-many” cultures are not atavistic holdouts from the Paleolithic, but the ways they experience the passing of time seem to reflect the ways that most people experienced time for most of our species’ existence. Minutes and seconds did not really influence European life until the usage of accurate clocks in church towers became widespread in the 15th and 16th centuries. Pendulum-based clocks and spring-loaded watches were invented and refined in the 17th and 18th centuries, bringing minutes and seconds to the masses.
These inventions facilitated the coordination of labour that proved critical to the Industrial Revolution and enabled better navigation. They also made our perception of time less natural. Our construal of time came to revolve around quantitatively based cultural conventions like minutes and seconds, becoming less centred around natural rhythms like the diurnal cycle. Precise measurement of time also advanced science and our understanding of time itself. Einstein’s proof of the relative nature of elapsed time was based on the constancy of the speed of light, which he knew to be about 300,000 km per second.
Perhaps the most interesting cultural differences surrounding time-sense are not related to numbers, but to how we turn time into space. English speakers often speak of past events as though they are “behind” the speaker while future events are “ahead” of them. In contrast, speakers of Aymara in the Andes refer to the future as being behind them, while the past is in front. (This makes sense, in a way, since we can more clearly “see” what happened in the past.)
The Yupno of New Guinea refer to the past as being downhill, the future as uphill. Such diverse perspectives surface in gestures, too: When English speakers talk about past events they often point backwards, while Aymara speakers point forwards. The Yupno point downhill when discussing past events, regardless of the direction they are facing while speaking.
Being human does not require the usage of precise temporal measurements, nor does it require that we even think of time in the same ways when we are not measuring it. Time is fundamental to our lives but discriminated in culturally dependent ways.
The radical variability in how humans construe time illustrates the extent to which communicative conventions can profoundly impact our lives. More and more, cross-cultural research on time and other basic facets of life is demonstrating the human experience is more varied than often assumed. The exploration of cultural and linguistic variation is critical to advancing our understanding of others and ourselves. Continuing this exploration is well worth our time.